Hi all, I have been redirected in here after posting my personal measurement-brainstorming on the 'discuss' list:
http://www.mail-archive.com/[EMAIL PROTECTED]/msg08902.html Despite being totally unaware of this thread, my reasoning seems to fit for the most part in the ongoing discussion, I believe there is one big issue that has been totally forgotten thought: in many contexts (scientific/technical) a measurement has no meaning without a corresponding error/confidence! thus, something like <span class="data-error">0.1</span> should find its place inside hmeasure ( hWhateverWillBe), actually this can be simplified by exploiting the '±' html-entity to signal the beginning of the error-value part, in place of the extra <span class="data-error> The correct measurement notation on paper is normally (absolute_error): ( 5.8 +/- 0.4 ) km. i.e. the 2 values must be expressed in the same unit and with the same precision (number of digits). This is far more important than requiring that the string used for the unit-measure conforms with SI standard. As long as the 2 values are consistent (as defined above), they represent a valid data-entry in some unit, and the parser's should just 'export' (*). another notation is (relative_error): 5.8 Km. +/- 7% error propagation on derived quantities is computed by algebraic rules on relative_errors, than converted back to the absolute_error notation. Sorry for the cheap 101-lesson in Experimental Science & Statistics! (*) Verifying strict SI-conformance is not that important for the entry in itself, it does get crucial when comparing and combining entries, but I believe this is a separate computing layer and the initial hmeasure specs can go soft about it. For example let's imagine a 'universal unit-conversion Firefox extension', it would definetly exploit the hmeasure parser, but would have to take care of unit-validations on its own, once it gets the data entries from the parser. _______________________________________________ microformats-new mailing list [email protected] http://microformats.org/mailman/listinfo/microformats-new
